[The following is taken from a note in Ileia Newsletter, vol 9, # 3, p. 31. See EDN 42-6 for a review of this newsletter.] “In Keralea (southern India) fruit fly (Dacus dorsalis and D. cucurbitae) incidence is severe in mango trees. P. Reghunath and M. Indira describe a low-cost technology to combat this insect pest.”
A fruit fly trap is prepared as follows. “20 g of Ocimum sanctum (holy basil) leaves are crushed and the extract together with the crushed leaves are placed inside a coconut shell, which is then filled with 100 ml water. To increase the keeping quality of the extract, 0.5 g citric acid is added and the extract is then poisoned by mixing 0.5 g carbofuran 3G. The traps are suspended from mango tree branches at a rate of 4 traps per tree. The fruit flies feed on the ocimum extract and are killed in a few minutes. In our trial, over a hundred flies per week were caught in this way.
"To successfully control pests we advise an integrated strategy. Set the traps in the trees at the above rate, as soon as fruit set begins and continue till harvest. Change the traps every week and set fresh traps. When the population of flies is heavy, give a spray with malathion 0.1% and sugar 2%. Collect and destroy attacked fruits that rot and drop down.”
ECHO Staff 1994. Fruit Fly Trap Made From Basil. ECHO Development Notes no. 44